Woven gauze has long been accepted as the standard material for constructing surgical sponges, swabs, dressings, bandages and similar products. The arrangement of yarns in the woven fabric provides a lightweight open structure which is folded to form multi-ply pads. Cotton fiber is used almost exclusively to make the yarn and confers characteristic properties such as absorbency and strength to the fabric. As a consequence of these properties, woven gauze is a versatile fabric used for many different purposes. Gauze sponges and swabs are used to absorb fluid, scrub and clean surfaces, remove dead cells and necrotic tissue (debride), separate tissues and organs (blunt dissection), pack and wall-off cavities, cover and protect organs and tissues during surgery and dress wounds. Gauze may be impregnated with various agents such as betadine (prepping) or petrolatum (dressing) for special applications.
The wet strength of gauze is important when the fabric is used in surgery for holding, lifting and moving organs and even skeletal structures. The low resilience of woven gauze permits the sponges to be packed in cavities or formed into shapes such as points for use in delicate surgery, and assures that the sponges will stay in place as positioned by the surgeon or nurse.
Despite its versatility and application in so many different procedures, there are several undesirable characteristics of conventional woven gauze that can have serious consequences during the use of the fabric in surgery. One such characteristic of gauze fabric is the tendency to shed lint particles. Gauze consists of a loose array of parallel warp yarns interwoven with fill yarns perpendicular to the warp direction. Yarn and fiber fragments are formed during the various operations of slitting, cutting and converting the fabric. Any particles remaining in the finished end product can easily separate from the fabric and contaminate wound and surgical sites.
There is no practical way for cutting gauze in either the warp or fill direction to completely avoid damaging yarns adjacent to the cut. Yarn fragments and even full lengths of yarn close to the cut can easily separate from the structure when the material is used. For this reason, gauze sponges are usually folded so that the cut edges are in the center and remain covered by fabric when the sponge is opened for use. If the user unfolds the sponge and exposes the cut edges, the incidence of linting is significantly increased.
The cotton fiber used to make the yarn is another source of lint. Not only does the initial cotton fiber length vary, but individual fibers are broken as the fiber is carded or combed and twisted together to form the yarn. In the yarn, the fibers are held together only by surface interaction and cohesive forces and many fiber ends protrude from the yarn. Since individual fibers are not firmly secured in the yarn and the yarn may be further degraded during subsequent processing (bleaching, scouring and drying), short fibers and fiber fragments may separate from the individual yarns during use.
Another deficiency of conventional woven gauze is the lack of physical and dimensional stability. When the fabric is worked either dry or wet as by folding, rolling, packing, wringing or pulling, the yarns are able to move independently of one another. Under stress, the yarns move and one displaced do not return to their original position after the stresses have been relaxed. Gauze has very poor burst properties because the yarns move and separate to form a hole in the fabric before they break. Thus the structure of woven gauze is easily deformed and disrupted by the stresses encountered in use. At extremes of stress during use, the integrity of the fabric can be completely destroyed with yarn and fiber fragments separating from the structure.
Griswold, U.S. Pat. No. 2,860,068, has shown that loosely woven structures such as gauze can be stabilized by applying a binder to the fabric in such a way that at least 20% of the warp and fill yarn intersections are bonded together. Gauze stabilized in this way was used as a facing fabric for sanitary napkins. However, the binder adversely affects absorbency and causes the fabric to become stiff, especially at higher levels of application where up to 50% of the yarn intersections may be bonded together, rendering such bonded gauze less desirable for use in sponges and other surgical products.
It is accordingly an object of the present invention to provide an improved woven gauze fabric for use in surgical applications. It is a further object to provide a gauze fabric having improved dimensional stability, integrity and handling properties. Another object of the present invention is to provide a gauze fabric having improved fluid absorption properties. A further object of the invention is to provide a novel stabilized fabric comprising a loosely constructed fabric of spaced apart yarns wherein intersecting yarns are anchored by staple fibers entangled about the yarns at the intersections thereof, and a method for preparing such stabilized fabric.